CVE WatchJul 15, 2026

CVE-2026-42055

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability e

CVSS

8.1

High

EPSS

3.6%

p88

KEV

—

Exploit Today

0-100

Published: Jun 17, 2026 · Last modified: Jul 15, 2026 · CWE-122 · CWE-787 · CWE-131

EPSS · 30d

2.8%EPSS · 30 days3.6%

2026-06-302026-07-16

Technical description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Official references

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